Holy CrystalsIn the town go to the bottom left building. There will be stairs. Go up them. There will be a spot to get in the chimney. Keep going down that intil you clear all the dust. Once this happens the goddes will come down and give you the recipe for holy crystals.

Unlock the Schwarzen Tank for Tank Masters modeTo unlock Slival's tank, the Schwarzen, for Tank Masters mode, you must first beat the final boss. Then, go to the place where you fought Slival on Mt. Krakatroda. Defeat him again (He will have 3000 HP) and you will unlock the Schwarzen.

Unlock Giggles for Tank Masters modeTo unlock the cyclops-themed tank Giggles for use in Tank Masters mode, you must first beat the game. Then, talk to the slime named Meggan, and it will be unlocked. Meggan is a green Egg Slime located in the northwest building of the central part of town.

Unlock the Gott Schliemen for Tank Masters modeTo unlock the Gott Schliemen for use in Tank Masters mode, first, beat the final boss and rescue all 100 slimes. Then, beat the final round of Tank Masters mode (against Hooly and the Shogun).